The invention relates to a carrier reproducing circuit for extracting the carrier signal from a pulse-coded continuous phase-modulated carrier signal having a rational modulation index, this circuit comprising a clock pulse regenerator, a multiplier having a multiplication factor N(N=2, 3, . . . ) for generating an N.sup.th harmonic from the modulated carrier signal, a first bandpass filter, coupled to the multiplier for isolating the aforesaid N.sup.th harmonic and a divider having the dividend N connected to the first bandpass filter.
Such a carrier reproducing circuit for extracting the carrier signal from a pulse-coded continuous phase-modulated carrier signal is known inter alia from the article entitled "Synchronization properties of continuous phase modulation" by J. Aulin and C. E. Sundberg, published in the "Conference Papers" of "Globecom 82, Global Telecommunication Conference, Miami, Nov. 29-Dec. 2, 1982.
Continuous phase modulation is used because the modulated carrier signals have a constant amplitude enabling non-linear amplification, and because they usually have a small bandwidth. This modulation category comprises among others Tamed Frequency Modulation (TFM), Quadrivalent Three-bit Correlated Cosinusoidal Modulation (Q3RC) and Correlative Phase Shift Keying (CORPSK).
It has appeared that a large jitter value commonly occurs in a carrier signal extracted in the way described hereinbefore.
The invention has for its object to strongly reduce in a simple manner the jitter effect occurring when reproducing a carrier signal from a continuous phase-modulated carrier signal.